1. Field
The present disclosure relates to a wide angle lens system, and more particularly, to a wide angle lens system including a focus lens group that is lightweight, and an electronic apparatus having the wide angle lens system.
2. Description of the Related Art
Currently, digital cameras or video cameras having a solid state imaging device such as a charge coupled device (CCD) or a complementary metal-oxide semiconductor (CMOS) device are becoming widely popular. In particular, interchangeable-lens cameras are in high demand.
As demand for cameras increases, demand for single focus lenses such as a telephoto lens or a wide angle lens is also increased. A wide angle lens including a so-called retrofocus lens having a long back focal length, a first lens group having negative refractive power, and a second lens group having positive refractive power sequentially arranged from an object side is well known.
The retrofocus lens system may have a long back focal length and a wide viewing angle. However, currently, a so-called auto focusing optical system for performing auto focusing by driving a focus lens group using a motor is used frequently in still cameras and video cameras. In an auto focusing optical system, a focus lens group needs to be lightweight in order to rapidly perform focusing. However, a wide angle lens system may not easily have a large diameter and a lightweight focus lens group at the same time.